Agricultural harvesting machines, and particularly, large machines such as combines, commonly utilize an elongate axle or cross member extending sidewardly through or beneath a frame or chassis of the machine, on the opposite ends of which axle or cross member wheels are mounted for supporting the machine. In a combine, the forward wheels are commonly the primary drive wheels, and support the bulk of the weight of the machine, including a grain tank disposed thereabove which can be quite heavy when loaded with grain, as well as a header mounted on the front end of the machine, which can also be quite large, necessitating a particularly large and robust axle or cross member extending across the machine.
Many agricultural operators presently desire combines that have greater harvesting and grain processing and handling capacity. However, this presents a substantial design challenge, as the overall size envelope into which a combine must fit is limited by width restrictions for passage over public roads, thoroughfares, bridges and the like, by height restrictions for passage under overhead wires and through doors of storage and service buildings, and trailer transport restrictions. A necessary component of the grain processing and handling apparatus of a combine is a cleaning fan used to generate a rearwardly directed flow of air to sieves of a cleaning system for removing material other than grain from the grain itself before it is conveyed to the grain tank or offloaded. The cleaning fan is typically enclosed or housed in a wrapper disposed between the sides of the frame or chassis, near the front axle or cross member. Increasing axle weight bearing capacity, particularly by increasing the vertical extent thereof, and, at the same time, increasing grain processing and handling capability, particularly cleaning fan output, can result in competing demands on limited interior space.
As another challenge, as the harvesting and grain processing and handling capacity of a combine are increased, there can be a tendency for complexity, e.g. the number of components, weight and cost to also increase, which can be a disadvantage costwise.
Thus, what is sought is axle and cleaning fan constructions for an agricultural harvesting machine which meets at least one of the challenges and overcomes one of the problems and disadvantages discussed above.